Electrocardiogram – Procedure, Purpose & Results

What is an ECG?

ECG (Electrocardiogram) is a machine that measures the heart rate and its rhythm. The electrocardiogram test is a quick test to check your heart health, and it is also pain-free. ECG is a graphic record produced by an electrocardiograph that provides details about heart health, heart rate, and it’s rhythm. Test results from ECG can help in diagnosing a heart attack, abnormalities or irregular heartbeat. 

The human heart produces an electrical impulse that passes our heart and reaches our skin. ECG machines use those electrical impulses and make a graph out of them. The electrical activities of the heart cause the heart muscles to contract, which is the result of heart pumping. Heartbeats are in the form of skips and dips, which are known as waves, and those waves are the form on the graph that shows heart health. 

ECG machines are mostly found in operation rooms, medical offices, hospitals, and ambulances. There are some personal devices available, too, like smartwatches, which can also do simple ECGs. 

How does an ECG work?

An electrocardiogram is one of the fastest and easiest tests for evaluating heart health. An ECG machine is connected to humans with the help of electrodes, which are small, plastic patches that stick to the skin. Electrodes are placed on the certain places on your chest, legs and arms, those electrodes are then connected to ECG machine via lead wires and then the electric activity of heart is measured and printed out. In this whole process no electricity is sent into body. 

Mainly, An ECG records the impulses of how fast or slow heart is beating. At every beat, heart undergoes a triggered contraction and those electrical activities are passes throughout the body and can be tracked via skin. This is the basic mechanism of ECG. Basically ECG machine documents the activity of heart via electrodes stick on the skin and represent it graphically. 

Electrocardiogram test

The electrocardiogram test is mainly used to check the heart rhythm via electrical movements. Those electric signals are detected through the attached sensors on the skin, which give a signal when the heart beats. These electric signals are then tracked by the machine and printed out. Finally, these results are examined by doctors so that you can understand them. There is more than one type of ECG performed by health care. 

Types of ECG test

Three main types of ECG tests are performed.

Resting ECG

Resting ECG is the most common type of ECG test performed in hospitals and health care centres. It mainly involves attaching electrodes to your chest, legs and arms for the results. In a resting ECG test, you need to lie down on your back; it is important to stay calm and comfortable during the test. It is important to know that NO movements are allowed during the test because testing your muscles, coughing, moving, or shaking can affect the results. Usually, this test takes only 10 minutes, and accurate results can be recorded only if you stay calm. 

Exercise/Stress ECG

Exercise ECG helps the doctor to see how well your heart is working during physical activity. It mainly involves having an ECG test while you are riding or walking on a treadmill. Stress tests sometimes involve medicine to understand the effect of a new medicine on the heart. Exercise ECG tests usually take 15 to 20 minutes. It is only done to measure the electrical activity of your heart when doing physical activity. During this test, your blood pressure is also checked regularly. While the ECG is going on, if any irregularities occur in the test, it immediately stops.

Ambulatory ECG

In ambulatory ECG, the electrical activities of the heart are recorded over 24 hours . In this ECG test, three to four electrodes are stuck to your chest, and a small recording device is worn around your neck or worn like a belt to take a continuous record of your activity. Then, the ECG data is transferred to a computer for doctors to analyse later. When you are wearing a Holter monitor, it is important to track your daily activities because the doctor needs information to analyse the ECG result. 

Why is ECG done?

The main purpose of an Electrocardiogram is to check the rhythm of your heart. An ECG test mainly shows how fast or slow your heart is beating. It also tracks irregular heartbeats and previous heart attacks and causes chest pain. An ECG is also prescribed to learn how well a pacemaker or heart disease treatment is working. 

You may need electrocardiogram for:

• Chest pain
• Dizziness
• Skipping or fluttering heartbeat
• Weakness or fatigue
• Fast pulse
• Shortness of breath
• Pounding
• Reduced ability to exercise

Result of an ECG

When your ECG is done, your results will be printed on paper, or the data will be transferred to the doctor’s computer. Small patches(Electrodes) will be attached to your chest, arms, and legs in several places. Then, those patches will get connected to the machine via lead wire. When the machine gets started, it will produce wave lines on a piece of long paper in the form of a graph. Those graphs are the representation of electric signals coming from your heart. So, if the test is normal, you will see your heart beating at an even rate of 60 to 100 beats per minute. ECG can show you heart conditions like beating fast, slow or abnormal heart rhythm; it can also show if you had a heart attack in past or any heart disease. 

If you have a personal or family history of heart disease, you may need to take an ECG on a regular basis or consult your doctor about it, but if there is no such heart disease history in your family or you have never had a heart-related problem than you don’t have to worry about daily ECG test. An ECG mostly shows the accurate diagnosis of many heart diseases, but sometimes it can’t pick up every heart problem, so the doctors can ask for other tests, too. 

How to prepare for an ECG?

For ECG test you don’t have to get prepare before hand but there are some points that you need to keep them in your mind.

• First of all, your technician or the healthcare provider will explain the whole thing about the test; if you don’t understand anything, you can ask questions related to the test.
• Like another test, fasting is not required before the test.
• Make sure your provider knows all about the medication, supplements, and vitamins you take.
• Tell your healthcare provider if you have a pacemaker so they can work accordingly.
• Based on your condition, the person may request that you have some specific preparation before. 
• Make sure not to exercise or drink cold water just before the ECG test, as it may cause false results. 

What happens during the electrocardiogram test?

An ECG is done on a patient basis on the condition of the person, or the steps vary according to your healthcare provider’s practices. 

Generally, an ECG follows some basic steps like:

• At first, you will be asked to remove all your jewellery or other items that may interfere with the test. 
• Then you will be asked to remove clothing from the waist up, and a sheet or gown will be provided by the technician to wear so the necessary skin is only exposed during the test. 
• You have to lie flat on the table, and it is important to stay still and not talk during the test so you can get accurate results. 
• Then, the provider will stick the electrodes to certain places on your chest, arms and legs. 
• Then, the lead wire will be attached to the electrodes.
• Once everything is set, the technician will insert the information into the machine’s computer
• The ECG will start, and it will only take a short time for tracing to complete and print the given result.
• Once everything is done, the technician will disconnect the leads and remove the electrodes from your skin. 

Conclusion

ECG or Electrocardiogram test is mainly used to check your heart health. Whereas the accuracy of ECG depends on the condition being tested, some heart problems may not be shown on the ECG, as some heart conditions never produce any specific wave changes to be tracked on ECG. 

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